3 Egg yolks
50g butter (unsalted)
1 tablespoon water
1 tablespoon lemon juice
1 pinch cayenne
Start by melting the butter in a small saucepan. In a bowl, whisk together the yolks, water, lemon juice and cayenne. Put the bowl over a pan with simmering water, it must not be boiling too much, since this can help the sauce to split.
Now start whisking and do not stoop for the next 5 minutes. Gradually add the butter into the mixture, a little at a time. Once all the butter is incorporated you have smooth, velvet-like sauce. The Hollandaise.
Note on the side: Keep an ice cube ready when mixing in the butter. If it starts to split, just whisk it in and it might save the sauce.